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601.
Over the years, many different techniques have been used to treat brain aneurysms. Traditionally, open surgery or craniotomy was required for aneurysm clipping, but since the mid 1980s the endovascular treatment of aneurysms has become increasingly popular. The mainstay of endovascular aneurysm treatment has been embolization with platinum coils (a.k.a. “coiling”). However, despite advances in endovascular techniques, such as balloon remodeling and intracranial stent placement, it remains difficult to achieve the complete and permanent occlusion of many broad-based saccular aneurysms. Onyx HD-500 (eV3 Neurovascular, Irvine, CA), a liquid embolic agent, is the latest Food and Drug Association-approved device to be used in attempt to overcome the challenge of occluding broad-based intracranial aneurysms.In this case study, we describe the clinical and procedural issues involved in the treatment of a patient with a large, symptomatic intracranial aneurysm using Onyx HD-500.  相似文献   
602.
本刊经Philip M.Meyers博士代表写作组授权,将“ Reporting standards for angioplasty and stent-assisted angioplasty for intracranial atherosclerosis”译为中文在本刊刊登。标准中对患者的选择、颅内动脉狭窄程度的判断、最佳内科治疗、围手术期处理、血管内治疗、术后并发症等,进行了规范化总结,拟为今后的临床试验和研究的规范化确定标准,以保证结果的可比性,对神经介入医师具有重要的指导意义。  相似文献   
603.

Background

Risks for methicillin‐resistant Staphylococcus aureus (MRSA) among those with HIV infection have been found to vary, and the epidemiology of USA‐300 community‐acquired (CA) MRSA has not been adequately described.

Methods

We conducted a retrospective review of HIV‐infected out‐patients from January 2002 to December 2007 and employed multivariate logistic regression (MLR) to identify risks for MRSA colonization or infection. Pulsed‐field gel electrophoresis (PFGE) was used to identify USA‐300 strains. Results Seventy‐two (8%) of 900 HIV‐infected patients were colonized or infected with MRSA. MLR identified antibiotic exposure within the past year [odds ratio (OR) 3.4; 95% confidence interval (CI) 1.5–7.7] and nadir CD4 count <200 cells/μL (OR 2.5; 95% CI 1.2–5.3) as risks for MRSA colonization or infection. Receipt of antiretroviral therapy (ART) within the past year was associated with decreased risk (OR 0.16; 95% CI 0.07–0.4). Eighty‐nine percent of available strains were USA‐300. MLR identified skin or soft tissue infection (SSTI) as the only predictor for infection with USA‐300 (OR 5.9; 95% CI 1.4–24.3). Conclusion Significant risks for MRSA among HIV‐infected patients were CD4 count nadir <200 cells/μL and antibiotic exposure. Only the presence of an SSTI was associated with having USA‐300, and thus the use of patient characteristics to predict those with USA‐300 was limited. In addition, ART within the previous year significantly reduced the risk of MRSA colonization or infection.
  相似文献   
604.
Selvanathan SK, Shenton A, Ferner R, Wallace AJ, Huson SM, Ramsden RT, Evans DG. Further genotype–phenotype correlations in neurofibromatosis 2. Neurofibromatosis 2 (NF2) is caused by mutations in the NF2 gene predisposing carriers to develop nervous system tumours. Different NF2 mutations result in either loss/reduced protein function or gain of protein function (abnormally behaving mutant allele i.e. truncated protein potentially causing dominant negative effect). We present a comparison between the clinical presentations of patients with mutations that are predicted to produce truncated protein (nonsense/frameshift mutations) to those that results in loss of protein expression (large deletions) to elucidate further genotype–phenotype correlations in NF2. Patients with nonsense/frameshift mutations have a younger age of diagnosis and a higher prevalence/proportion of meningiomas (p = 0.002, p = 0.014), spinal tumours (p = 0.004, p = 0.004) and non‐VIII cranial nerve tumours (p = 0.006, p = 0.003). We also found younger age of diagnosis of vestibular schwannomas (p = 0.007), higher mean numbers of cutaneous lesions (p = 0.003) and spinal tumours (p = 0.006) in these patients. With respect to NF2 symptoms, we found younger age of onset of hearing loss (p = 0.010), tinnitus (p = 0.002), paraesthesiae (p = 0.073), wasting and weakness (p = 0.001) and headaches (p = 0.049) in patients with nonsense/frameshift mutations. Our comparison shows, additional, new correlations between mutations in the NF2 gene and the NF2 disease phenotype, and this further confirms that nonsense/frameshift mutations are associated with more severe NF2 symptoms. Therefore patients with this class of NF2 mutation should be followed up closely.  相似文献   
605.
606.
Minoru Nakagawa  MD    Kenji Sugiu  MD    Koji Tokunaga  MD    Kohei Tsuda  RT    Matsuhiro Imaoka  RT    Atsushi Kawahara  RT    Kenjiro Fujiwara  MD 《Journal of neuroimaging》2009,19(2):179-182
The authors reported a case of a dural arteriovenous fistula (DAVF) in the left transverse-sigmoid sinus, in which 3-dimensional computed tomography (CT) angiograms (3D-CTAs) by a 64-section multidetector row CT scanner were useful for its diagnosis and treatment. The DAVF in the left transverse-sigmoid sinus appeared on the digital subtraction angiogram. 3D-CTAs were obtained by a 64-section multidetector row CT scanner before an endovascular treatment. The feeders and draining veins of the DAVF were clearly demonstrated on the 3D-CTAs, which clarified the relationship between the normal dural sinuses and DAVF. The DAVF was successfully treated with endovascular surgery, a transvenous embolization through the mastoid emissary vein, which was easily detected by using the 3D-CTA, showing both the subcutaneous vein and calvalium. 3D-CTAs by a 64-section multidetector row CT scanner are useful for both diagnosis and treatment of DAVFs.  相似文献   
607.
Although dementia is increasingly recognized as a common feature in Parkinson's disease (PD), its pathological substrate remains unknown. We conducted cross‐sectional and longitudinal brain perfusion SPECT analyses to explore changes during the course of developing dementia in PD. Fifty‐five patients originally diagnosed with PD were imaged in the cross‐sectional study. Twenty‐one of these, nine without dementia and 12 with dementia (PDD), were included in the longitudinal study to observe perfusion changes during the course of their disease. Data were analyzed using three‐dimensional stereotactic surface projection SPECT analysis. The UK Parkinson's Disease Society Brain Bank criteria were used to diagnose PD and the revised criteria for the clinical diagnosis of dementia with Lewy bodies for PDD. The cross‐sectional study showed that patients with PDD had significantly reduced perfusion in the right posterior cingulate, the right precuneus and the left posterior cingulate area. In the longitudinal study, significantly reduced perfusion was observed in the left anterior frontal gyrus in PD without dementia, and in the right inferior parietal lobule in those that developed PDD. We suggest that a relationship exists between developing dementia in PDD and reduced perfusion in the posterior parietal area. © 2009 Movement Disorder Society  相似文献   
608.
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